Effects of the Zimbabwe Defence Forces training programme on body composition and reproductive hormones in male army recruits.

OBJECTIVES: To investigate the effects of a four month endurance training programme on body composition and reproductive hormone levels.

DESIGN: PRE and POST training comparative study.

SETTING: Zimbabwe Military Academy, Gweru, Zimbabwe.

SUBJECTS: 77 male recruit volunteers participating in the Zimbabwe Defence Forces cadet training programme.

MAIN OUTCOME MEASURES: Percent body fat, fat free mass, body mass index, total serum testosterone, luteinising hormone (LH) and follicle stimulating hormone (FSH) compared using the paired t-test.

RESULTS: There was a significant decrease in all parameters measured after four months of endurance training. Decreases in body composition parameters were 54% in percent body fat, 6% in fat free mass, and 13% in body mass index. There was a dramatic 58% drop in testosterone, 60% drop in LH and 15% drop in FSH after four months of endurance training.

CONCLUSIONS: The Zimbabwe Defence Forces cadet training programme, an endurance training programme induces a state of negative energy balance in trainees. This results in a decrease in % body fat and body mass index due to utilisation of fat stores as a source of energy and a decrease in fat free mass due to gluconeogenic utilisation of muscle protein as energy source for muscle activity. There is impaired hypothalamic-pituitary-testicular axis function as evidenced by the state of hypogonadal-hypogonadism (low testosterone, LH and FSH). This may be attributed to: 1. gonadotrophin releasing hormone pattern generator malfunction due to the stress of intense physical activity and 2. withdrawal of energy expenditure from reproductive machinery as a way of conserving energy for more vital processes in the prevailing state of energy starvation.